The present invention relates to a multi-channel broadcasting program system, and more particularly, to a method for performing channel scan within a multi-channel broadcasting program receiver, and to an associated multi-channel broadcasting program receiver.
Portable multi-channel broadcasting program systems such as television (TV) receivers implemented within portable devices or add-on modules have become popular since there are many attractive characteristics for user's convenience, such as portability and high flexibility. As the users may operate the portable multi-channel broadcasting program systems at different locations, and as the channels available at respective locations are not all the same, a channel scan operation is required for detecting the channels available at a specific location in advance. According to the related art, a channel scan operation is typically performed by searching video carrier signals from a predetermined lower frequency band through to a predetermined upper frequency band of a plurality of frequencies intervened with the same predetermined frequency step, whose size can be referred to as the frequency step size.
Please note that, in contrast to the range of the frequencies to be searched, the frequency step size is very small. For example, the frequency step size typically ranges from 50 KHz to 500 KHz. However, the frequencies to be searched typically ranges from 45.25 MHz through to 873.25 MHz. As a result of applying the conventional channel scan method to the portable multi-channel broadcasting program systems, it usually takes too much time to find out the frequencies of all possible carriers, while only a portion of possible carriers are correct video carriers. Users may feel annoyed and may become impatient since they always need to wait for a long time to watch TV/listen to program when traveling to a new location.
In conclusion, the conventional channel scan operation does not serve the user well, and a novel method and an associated multi-channel broadcasting program receiver are required to speed up the channel scan operation.